Wear Properties of Conventional and High-Translucent Zirconia-Based Materials

Abstract

This study investigated the two-body wear resistance of a first generation 3 mol% yttria-stabilized tetragonal zirconia polycrystal (3Y-TZP), a second generation 3Y-TZP, a third generation 4 mol% yttria partially stabilized zirconia (4Y-PSZ), a 5 mol% yttria partially stabilized zirconia (5Y-PSZ), and a type III gold alloy (Aurocast 8), performed using opposing antagonistic cusps made out of the same material. Eight cylindrical specimens were prepared for each material (n = 8) for a total of forty specimens (N = 40). Conical cusps were fabricated for each material. Each cylinder–cusp pair was arranged inside a two-axis chewing simulator over up to 360,000 loading cycles. The wear resistance was analyzed by measuring the vertical substance loss (mm) and the volume loss (mm3). The antagonist wear (mm) was recorded before and after the wear test to evaluate the linear difference. Statistical analysis was performed using one-way analysis of variance (ANOVA); multiple comparisons were performed according to Tukey’s method. No statistically significant differences (p > 0.05) among the first generation 3Y-TZP, second generation 3Y-TZP, and 4Y-PSZ wear were found. 5Y-PSZ showed statistically significant higher wear compared to other the zirconias. Aurocast 8 displayed the highest values in terms of vertical wear, antagonist cusp wear, and volumetric loss. Although still not statistically comparable, the wear behavior of the latest 5Y-PSZ was the closest to the widely recognized gold standard represented by the type III gold alloy.

Mechanical Properties of Translucent Zirconia: An In Vitro Study

“…The author reported that the polished zirconia produced less abrasion than glazed zirconia or polished feldspathic ceramic. Recently, De Angelis et al [64] reported a wear resistance for the ultra-translucent zirconia closest to that of type III gold alloy. On the other hand, Albashaireh et al [65] showed how the degree of wear of the antagonist tooth enamel was significantly less in zirconia restorations compared to feldspar porcelain restorations.…”

Effect of the Abutment Rigidity on the Wear Resistance of a Lithium Disilicate Glass Ceramic: An In Vitro Study

“…Dental implants used to restore missing teeth do not have periodontal ligament nor mechanoreceptors and are not able to move in the bone, which means that the natural mechanisms of adapting to occlusion do not function in their case [ 23 ]. Crowns on implants made of ceramic materials or zirconium oxide are additionally characterized by greater hardness and a lower modulus of elasticity [ 24 ] as well as lower ability to wear than natural human enamel [ 25 , 26 ].…”

“…Several papers investigated the in vitro wear resistance of restorative materials opposing either human enamel antagonists or dedicated artificial abraders [ 25 , 46 ], underlining the effect of different antagonist materials on the wear rate of tested specimens. Furthermore, few studies analyzed the wear behavior of dental materials opposing themselves, which seems particularly interesting for simulating the clinical scenario of restored occlusal surfaces occluding in a full-mouth rehabilitation [ 26 , 47 ].…”

Wear of lithium disilicate opposed by various ceramic materials

“…Dental zirconia is available in various compositions (3–5 mol% yttria‐stabilized) which affect its mechanical and physical properties 10 . A cusp‐on‐cylinder 2‐axis wear study of various ceramics opposing themselves reported that 5 mol% yttria‐stabilized (5Y) zirconia experienced more wear than 4Y or 3Y zirconia 11 …”

“…10 A cusp-on-cylinder 2-axis wear study of various ceramics opposing themselves reported that 5 mol% yttria-stabilized (5Y) zirconia experienced more wear than 4Y or 3Y zirconia. 11 Therefore, the main objective of this study was to measure and compare the wear of lithium disilicate opposed by various restorative materials (3Y zirconia, 5Y zirconia, lithium disilicate, and feldspathic porcelain) and enamel. Microhardness and scanning electron microscopy were performed to help understand the mechanisms of wear.…”